Strange comment from (our less than favorite) controller after departing saying "don't hit the Tower please", Mode C apparently never received, then he returned about 15 minutes after departing, the scanner never picked up his signal, (either he was too low or too weak.) Witness reports seeing him in a right turn on final 100-200 feet above the houses before the crash. Very busy, and Young Eagle rides going on at the same time. Departure, Arrival, and PD helo arrival on the recording, with silence removed. Glad they survived.